ANALOG DEVICES ADA4862-3 Service Manual

High Speed, G = +2,

www.BDTIC.com/ADI

FEATURES

Ideal for RGB/HD/SD video

Supports 1080i/720p resolution

High speed

−3 dB bandwidth: 300 MHz
Slew rate: 750 V/μs

Settling time: 9 ns ( 0.5%)

0.1 dB flatness: 65 MHz
Differential gain: 0.02%
Differential phase: 0.03°
Wide supply range: 5 V to 12 V
Low power: 5.3 mA/amp
Low voltage offset (RTO): 3.5 mV (typ)
High output current: 25 mA
Also configurable for gains of +1, −1
Power-down

APPLICATIONS

Consumer video
Professional video
Filter buffers

GENERAL DESCRIPTION

Low Cost, Triple Op Amp

ADA4862-3

PIN CONFIGURATION

POWER DOWN 1

POWER DOWN 2

POWER DOWN 3

+V

+IN 1

–IN 1

V

OUT

1

2

3

ADA4862-3

4

S

5

550Ω 550Ω

6

7

1

550Ω 550Ω

Figure 1. 14-Lead SOIC (R-14)

550Ω

550Ω

14

V

2

OUT

13

–IN 2

12

+IN 2

11

–V

S

10

+IN 3

9

–IN 3

8

V

3

OUT

05600-001

The ADA4862-3 (triple) is a low cost, high speed, internally
fixed, G = +2 op amp, which provides excellent overall
performance for high definition and RGB video applications.
The 300 MHz, G = +2, −3 dB bandwidth, and 750 V/μs slew
rate make this amplifier well suited for many high speed
applications. The ADA4862-3 can also be configured to
operate in gains of G = +1 and G = −1.

With its combination of low price, excellent differential gain
(0.02%), dif

ferential phase (0.03°), and 0.1 dB flatness out to
65 MHz, this amplifier is ideal for both consumer and
professional video applications.

The ADA4862-3 is designed to operate on supply voltages as
lo

w as +5 V and up to ±5 V using only 5.3 mA/amp of supply
current. To further reduce power consumption, each amplifier
is equipped with a power-down feature that lowers the supply
current to 200 μA/amp. The ADA4862-3 also consumes less
board area because feedback and gain set resistors are on-chip.
Having the resistors on chip simplifies layout and minimizes the
required board space.

Rev. A

Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Anal og Devices for its use, nor for any infringements of patents or ot her
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.

The ADA4862-3 is available in a 14-lead SOIC package and is
desig

ned to work in the extended temperature range of −40°C

to +105°C.

6.1

6.0

5.9
G = +2

5.8

R

= 150Ω

L

C

= 4pF

L

5.7

V

= 2V p-p

OUT

5.6

5.5

5.4

CLOSED-LOOP GAIN (dB)

5.3

5.2

5.1

0.1 1000

1 10 100

FREQUENCY (MHz)

VS = ±5V

Figure 2. Large Signal 0.1 dB Bandwidth for Various Supplies

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] www.analog.com
Fax: [phone] © 2005 Analog Devices, Inc. All rights reserved.

VS = +5V

05600-022

ADA4862-3

www.BDTIC.com/ADI

TABLE OF CONTENTS

Features .............................................................................................. 1

Applications..................................................................................... 11

Applications....................................................................................... 1

Pin Configuration............................................................................. 1

General Description......................................................................... 1

Revision History ............................................................................... 2

Specifications..................................................................................... 3

Absolute Maximum Ratings............................................................ 5

Thermal Resistance ...................................................................... 5

ESD Caution.................................................................................. 5

Typical Performance Characteristics ............................................. 6

REVISION HISTORY

8/05—Rev. 0 to Rev. A

Changes to Ordering Guide.......................................................... 15

7/05—Revision 0: Initial Version

Using the ADA4862-3 in Gains = +1, −1................................ 11

Video Line Driver....................................................................... 13

Single-Supply Operation ........................................................... 13

Power Down ................................................................................ 13

Layout Considerations............................................................... 14

Power Supply Bypassing ............................................................ 14

Outline Dimensions ....................................................................... 15

Ordering Guide .......................................................................... 15

Rev. A | Page 2 of 16

ADA4862-3

www.BDTIC.com/ADI

SPECIFICATIONS

VS = +5 V (@TA = 25oC, G = +2, RL = 150 Ω, unless otherwise noted).

Table 1.

Parameter Conditions Min Typ Max Unit

DYNAMIC PERFORMANCE

–3 dB Bandwidth VO = 0.2 V p-p 300 MHz
V

G = +1 VO = 0.2 V p-p 620 MHz
Bandwidth for 0.1 dB Flatness VO = 2 V p-p 65 MHz
+Slew Rate (Rising Edge) VO = 2 V p-p 750 V/μs

−Slew Rate (Falling Edge) VO = 2 V p-p 600 V/μs
Settling Time to 0.5% VO = 2 V step 9 ns

DISTORTION/NOISE PERFORMANCE

Harmonic Distortion HD2 fC = 1 MHz, VO = 2 V p-p −81 dBc
Harmonic Distortion HD3 fC = 1 MHz, VO = 2 V p-p −88 dBc
Harmonic Distortion HD2 fC = 5 MHz, VO = 2 V p-p −68 dBc
Harmonic Distortion HD3 fC = 5 MHz, VO = 2 V p-p −76 dBc
Voltage Noise (RTO) f = 100 kHz 10.6 nV/√Hz
Current Noise (RTI) f = 100 kHz, +IN 1.4 pA/√Hz
Differential Gain 0.02 %
Differential Phase 0.03 Degrees
Crosstalk

DC PERFORMANCE

Offset Voltage (RTO) Referred to output (RTO) −25 +3.5 +25 mV
+Input Bias Current −2.5 −0.6 +1 μA
Gain Accuracy 1.9 2 2.1 V/V

INPUT CHARACTERISTICS

Input Resistance +IN 13 MΩ
Input Capacitance +IN 2 pF
Input Common-Mode Voltage Range G = +1 1 to 4 V

POWER DOWN PIN

Input Voltage Enabled 0.6 V
Power down 1.8 V
Bias Current Enabled −3 μA
Power down 115 μA
Turn-On Time 3.5 μs
Turn-Off Time 200 ns

OUTPUT CHARACTERISTICS

Output Overdrive Recovery Time (Rise/Fall) VIN = +2.25 V to −0.25 V 85/50 ns
Output Voltage Swing RL = 150 Ω 1.2 to 3.8 V
Output Voltage Swing RL = 1 kΩ 1 to 4 V
Short-Circuit Current Sinking or sourcing 65 mA

POWER SUPPLY

Operating Range 5 12 V
Total Quiescent Current Enabled 14 16 18 mA
Quiescent Current /Amplifier Power down = +V
Power Supply Rejection Ratio (RTO) dB

+PSR +VS = 2 V to 3 V, −VS = −2.5 V −52 −55 dB

−PSR

= 2 V p-p 200 MHz

O

Amplifier 1 driven, Amplifier 2 output

ed, f = 1 MHz

measur

S

= 2.5 V, −VS = −2 V to −3 V

+V

S

Power Down pin = −V

S

−75 dB

0.2 0.33 mA

−49 −52 dB

Rev. A | Page 3 of 16

ADA4862-3

www.BDTIC.com/ADI

VS = ±5 V (@TA = +25oC, G = +2, RL = 150 Ω, unless otherwise noted).

Table 2.

Parameter Conditions Min Typ Max Unit

DYNAMIC PERFORMANCE

–3 dB Bandwidth VO = 0.2 V p-p 310 MHz

V

G = +1 VO = 0.2 V p-p 720 MHz
Bandwidth for 0.1 dB Flatness VO = 2 V p-p 54 MHz
+Slew Rate (Rising Edge) VO = 2 V p-p 1050 V/μs

−Slew Rate (Falling Edge) VO = 2 V p-p 830 V/μs
Settling Time to 0.5% VO = 2 V step 9 ns

DISTORTION/NOISE PERFORMANCE

Harmonic Distortion HD2 fC = 1 MHz, VO = 2 V p-p −87 dBc
Harmonic Distortion HD3 fC = 1 MHz, VO = 2 V p-p −100 dBc
Harmonic Distortion HD2 fC = 5 MHz, VO = 2 V p-p −74 dBc
Harmonic Distortion HD3 fC = 5 MHz, VO = 2 V p-p −90 dBc
Voltage Noise (RTO) f = 100 kHz 10.6 nV/√Hz
Current Noise (RTI) f = 100 kHz, +IN 1.4 pA/√Hz
Differential Gain 0.01 %
Differential Phase 0.02 Degrees
Crosstalk

DC PERFORMANCE

Offset Voltage (RTO) −25 +2 +25 mV
+Input Bias Current
Gain Accuracy 1.9 2 2.1 V/V

INPUT CHARACTERISTICS

Input Resistance +IN 14 MΩ
Input Capacitance +IN 2 pF
Input Common-Mode Voltage Range G = +1 −3.7 to +3.8 V

POWER DOWN PIN

Input Voltage Enabled −4.4 V
Power down −3.2 V
Bias Current Enabled
Power down
Turn-On Time 3.5 μs
Turn-Off Time 200 ns

OUTPUT CHARACTERISTICS

Output Overdrive Recovery Time (Rise/Fall) VIN = ±3.0 V 85/40 ns
Output Voltage Swing RL = 150 Ω −3.5 to +3.5 V
Output Voltage Swing RL = 1 kΩ −3.9 to +3.9 V
Short-Circuit Current Sinking or sourcing 115 mA

POWER SUPPLY

Operating Range 5 12 V
Total Quiescent Current Enabled 14.5 17.9 20.5 mA
Quiescent Current/Amplifier Power down = +V
Power Supply Rejection Ratio (RTO) dB

+PSR +VS = 4 V to 6 V, −VS = −5 V −54 −57 dB

−PSR

= 2 V p-p 260 MHz

O

Amplifier 1 driven, Amplifier 2 output

ed, f = 1 MHz

measur

−2.5 −0.6 +1 μA

S

= 5 V, −VS = −4 V to −6 V,

+V

S

Power Down pin = −V

S

−75 dB

−3 μA
250 μA

0.3 0.5 mA

+50.5 −54 dB

Rev. A | Page 4 of 16

ADA4862-3

www.BDTIC.com/ADI

ABSOLUTE MAXIMUM RATINGS

Table 3.

Parameter Rating

Supply Voltage 12.6 V
Power Dissipation See Figure 3
Common-Mode Input Voltage

±V

S

Storage Temperature −65°C to +125°C
Operating Temperature Range −40°C to +105°C
Lead Temperature JEDEC J-STD-20
Junction Temperature 150°C

The power dissipated in the package (P

) is the sum of the

D

quiescent power dissipation and the power dissipated in the die due
to the amplifier’s drive at the output. The quiescent power is the
voltage between the supply pins (V

= Quiescent Power + (Tota l D ri v e P o we r − Load Power)

P

D

⎛

()

D

S

IVP

SS

×+×=

⎜

2

⎝

) × the quiescent current (IS).

S

2

OUT

R

V

⎞

OUT

–

⎟

R

L

L

⎠

VV

Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.

THERMAL RESISTANCE

θJA is specified for the worst-case conditions, that is, θJA is
specified for device soldered in circuit board for surface-mount
packages.

Table 4. Thermal Resistance

Package Type θ

JA

14-lead SOIC 90 °C/W

Maximum Power Dissipation

The maximum safe power dissipation for the ADA4862-3 is
limited by the associated rise in junction temperature (T
the die. At approximately 150°C, which is the glass transition
temperature, the plastic changes its properties. Even
temporarily exceeding this temperature limit may change the
stresses that the package exerts on the die, permanently shifting
the parametric performance of the amplifiers. Exceeding a
junction temperature of 150°C for an extended period can
result in changes in silicon devices, potentially causing
degradation or loss of functionality.

Unit

) on

J

RMS output voltages should be considered.

Airflow increases heat dissipation, effectively reducing θ

.

JA

In addition, more metal directly in contact with the package
leads and through holes under the device reduces θ

.

JA

Figure 3 shows the maximum safe power dissipation in the

ackage vs. the ambient temperature for the 14-lead SOIC

p
(90°C/W) on a JEDEC standard 4-layer board. θ

values are

JA

approximations.

2.5

2.0

1.5

1.0

0.5

MAXIMUM POWER DISSIPATION (W)

0

–55 125–45 –35 –25 –15 –5 5 15 25 35 45 55 65 75 85 95 105 115

Figure 3. Maximum Power Dissipation vs. Temperature for a 4-Layer Board

AMBIENT TEMPERATURE (°C)

05600-036

ESD CAUTION

ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on
the human body and test equipment and can discharge without detection. Although this product features
proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy
electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance
degradation or loss of functionality.

Rev. A | Page 5 of 16

ADA4862-3

www.BDTIC.com/ADI

TYPICAL PERFORMANCE CHARACTERISTICS

8

G = +2
R

= 150Ω

L

7

C

= 4pF

L

V

= 0.2V p-p

OUT

6

5

4

3

CLOSED-LOOP GAIN (dB)

2

1

0

0.1 1000

1 10 100

FREQUENCY (MHz)

VS = ±5V

VS = +5V

05600-004

200 2.7

VS = +5V

100 2.6

V

= ±5V

S

= 5V

0 2.5

S

±V

OUTPUT VOLTAGE (mV)

–100 2.4

–200 2.3

G = +2
R

= 150Ω

L

= 4pF

C

L

V

= 0.2V p-p

OUT

TIME = 5ns/DIV

= 0V

S

= 5V, –V

S

+V

OUTPUT VOLTAGE (V)

05600-028

Figure 4. Small Signal Frequency Response for Various Supplies

8

G = +2
R

= 150Ω

L

7

C

= 4pF

L

V

= 2V p-p

OUT

6

5

4

3

CLOSED-LOOP GAIN (dB)

2

1

0

0.1 1000

1 10 100

FREQUENCY (MHz)

VS = +5V

VS = ±5V

Figure 5. Large Signal Frequency Response for Various Supplies

6.1

6.0

5.9
G = +2

5.8

R

= 150Ω

L

C

= 4pF

L

5.7

V

= 2V p-p

OUT

5.6

5.5

5.4

CLOSED-LOOP GAIN (dB)

5.3

5.2

5.1

0.1 1000

1 10 100

FREQUENCY (MHz)

VS = ±5V

VS = +5V

Figure 6. Large Signal 0.1 dB Bandwidth for Various Supplies

05600-012

05600-022

Figure 7. Small Signal Transient Response for Various Supplies

200

150

100

50

0

–50

OUTPUT VOLTAGE (V)

–100

–150

–200

CL= 9pF

CL= 4pF

CL= 6pF

G = +2
R

= 150Ω

L

C

= 4pF

L

V

= 0.2V p-p

OUT

= ±5V

V

S

TIME = 5ns/DIV

Figure 8. Small Signal Transient Response for Various Capacitor Loads

2.7
CL= 9pF

CL= 6pF

2.6

CL= 4pF

2.5

OUTPUT VOLTAGE (V)

2.4

2.3

G = +2
R

= 150Ω

L

= 0.2V p-p

V

OUT

= 5V

V

S

TIME = 5ns/DIV

Figure 9. Small Signal Transient Response for Various Capacitor Loads

05600-016

05600-014

Rev. A | Page 6 of 16

ADA4862-3

www.BDTIC.com/ADI

1.5 4.0

1.0 3.5
VS = +5V

0.5 3.0

= 5V

0 2.5

S

±V

–0.5 2.0

OUTPUT VOLTAGE (V)

–1.0 1.5

–1.5 1.0

VS = ±5V

G = +2
R

= 150Ω

L

= 4pF

C

L

= 2V p-p

V

OUT

TIME = 5ns/DIV

Figure 10. Large Signal Transient Response for Various Supplies

= 0V

S

= 5V, –V

S

+V

OUTPUT VOLTAGE (V)

05600-010

6
5
4
3
2
1

0
–1
–2
–3

OUTPUT AND INPUT VOLTAGE (V)

–4
–5
–6

0 1000

100 200 300 400 500 600 700 800 900

INPUT VOLTAGE × 2

V

OUT

TIME (ns)

Figure 13. Input Overdrive Recovery

VS = ±5V
G = +2

= 150Ω

R

L

= 4pF

C

L

f = 1MHz

05600-042

1.5

1.0

0.5

0

–0.5

OUTPUT VOLTAGE (V)

–1.0

–1.5

CL = 9pF

CL = 6pF

CL = 4pF

G = +2

= 150Ω

R

L

= 4pF

C

L

= 2V p-p

V

OUT

V

= ±5V

S

TIME = 5ns/DIV

Figure 11. Large Signal Transient Response for Various Capacitor Loads

4.0

3.5

3.0

2.5

CL = 9pF

CL = 6pF

CL = 4pF

05600-018

5.5

5.0

4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

OUTPUT AND INPUT VOLTAGE (V)

0.5
0

–0.5

0 1000

100 200 300 400 500 600 700 800 900

Figure 14. Output Ove

INPUT VOLTAGE × 2

V

OUT

TIME (ns)

rdrive Recovery

VS = 5V
G = +2

= 150Ω

R

L

= 4pF

C

L

f = 1MHz

05600-041

2.0

OUTPUT VOLTAGE (V)

1.5

1.0

G = +2

= 150Ω

R

L

= 4pF

C

L

V

= 2V p-p

OUT

= 5V

V

S

TIME = 5ns/DIV

05600-019

Figure 12. Large Signal Transient Response for Various Capacitor Loads

Rev. A | Page 7 of 16

ADA4862-3

www.BDTIC.com/ADI

1.5

1.0
V

OUT

0.5

(V)

IN

0

AND V

OUT

V

–0.5

–1.0

–1.5

050

V

IN

5 1015202530354045

TIME (ns)

VS = ±5V, +5V
G = +2
V

OUT

R

L

C

L

V

OUT

EXPANDED

= 2V p-p
=150Ω
= 4pF

20

15

10

5

0

–5

–10

–15

–20

EXPANDED (mV)

OUT

V

05600-043

1.5

1.0

0.5

(V)

IN

0

AND V

OUT

V

–0.5

–1.0

–1.5

5 1015202530354045

050

Figure 15. Settling Time Falling Edge

V

OUT

V

IN

V

OUT

EXPANDED

TIME (ns)

V

S

G = +2
V

OUT

R

L

C

L

Figure 18. Settling Time Rising Edge

= ±5V, +5V

= 2V p-p
= 150Ω
= 4pF

20

15

10

5

0

–5

–10

–15

–20

EXPANDED (mV)

OUT

V

05600-046

1600

G = +2
V

= ±5V

S

1400

R

= 150Ω

L

C

= 4pF

L

1200

1000

800

600

SLEW RATE (V/μs)

400

200

0

0 5.0

0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
OUTPUT VOLTAGE STEP (V p-p)

POSITIVE SLEW RATE

NEGATIVE SLEW RATE

Figure 16. Slew Rate vs. Output Voltage

100

10

G = +2
R

= 150Ω

L

= 4pF

C

L

V

OUT

= ±5V

V

S

= +5V

V

S

= 2V p-p

05600-005

800

G = +2
V

= 5V

S

700

R

= 150Ω

L

C

= 4pF

L

600

s)

μ

500

400

300

SLEW RATE (V/

200

100

0

0.5 1.0 1.5 2.0 2.5

0 3.0

OUTPUT VOLTAGE STEP (V p-p)

POSITIVE SLEW RATE

NEGATIVE SLEW RATE

Figure 19. Slew Rate vs. Output Voltage

0

G = +2
R

= 150Ω

L

C

= 4pF

L

–20

V

= 2V p-p

OUT

V

= ±5V

S

V

= +5V

S

–40

–60

05600-006

VOLTAGE NOISE (nV/ Hz)

1

10

100 1k 10k 100k 1M 10M

FREQUENCY (Hz)

100M

05600-037

Figure 17. Voltage Noise vs. Frequency Referred to Output (RTO)

Rev. A | Page 8 of 16

CROSSTALK (dB)

–80

–100

–120

0.1 1000

1 10 100

FREQUENCY (MHz)

Figure 20. Large Signal Crosstalk

05600-023

ADA4862-3

www.BDTIC.com/ADI

19

18

0

VS = ±5V

–10

–20

17

16

TOTAL SUPPLY CURRENT (mA)

15

4

567891011

Figure 21. Total Supply Current vs. V

20

19

18

17

16

15

14

TOTAL SUPPLY CURRENT (mA)

13

12

–40 125

–25–105 203550658095110

SUPPLY VOLTAGE (V)

SUPPLY

VS = ±5V

VS = +5V

TEMPERATURE (°C)

12

Figure 22. Total Supply Current at Various Supplies vs. Temperature

05600-026

05600-021

–30

–40

–50

POWER SUPPLY REJECTION (dB)

–60

–70

0.01

0.1 1 10 100

Figure 23. Power Supply R

0

VS = ±2.5V

–10

–20

–30

–40

POWER SUPPLY REJECTION (dB)

–50

–60

0.01 1000

0.1 1 10 100

Figure 24. Power Supply R

–PSR

+PSR

FREQUENCY (MHz)

ejection vs. Frequency

–PSR

+PSR

FREQUENCY (MHz)

ejection vs. Frequency

05600-051

1000

05600-052

Rev. A | Page 9 of 16

ADA4862-3

www.BDTIC.com/ADI

–50

G = +2

= 150Ω

R

L

= 4pF

C

L

–60

HD2

= ±5V

V

S

–70

–80

–90

DISTORTION (dBc)

–100

–110

04

123

fO = 10MHz

OUTPUT VOLTAGE (V p-p)

fO = 20MHz

fO = 5MHz

fO = 2MHz

fO = 1MHz

05600-049

Figure 25. HD2 vs. Frequency vs. Output Voltage

–50

G = +2

= 150Ω

R

L

–60

= 4pF

C

L

HD3

= ±5V

V

–70

S

–80

–90

–100

DISTORTION (dBc)

–110

–120

–130

04

fO = 20MHz

fO = 1MHz

123

OUTPUT VOLTAGE (V p-p)

f

fO = 2MHz

= 10MHz

O

fO = 5MHz

05600-054

Figure 27. HD3 vs. Frequency vs. Output Voltage

–50

G = +2

= 150Ω

R

L

= 4pF

C

L

–60

HD2

= 5V

V

S

–70

–80

–90

DISTORTION (dBc)

–100

–110

0 2.5

0.5 1.0 1.5 2.0

fO = 20MHz

fO = 10MHz

fO = 5MHz

fO = 2MHz

fO = 1MHz

OUTPUT VOLTAGE (V p-p)

Figure 26. HD2 vs. Frequency vs. Output Voltage

05600-050

–50

–60

–70

–80

–90

–100

DISTORTION (dBc)

–110

–120

–130

0 2.5

fO = 20MHz

f

= 10MHz

O

fO = 2MHz

fO = 1MHz

0.5 1.0 1.5 2.0
OUTPUT VOLTAGE (V p-p)

Figure 28. HD3 vs. Frequency vs. Output Voltage

fO = 5MHz

G = +2

= 150Ω

R

L

= 4pF

C

L

HD3

= +5V

V

S

05600-048

Rev. A | Page 10 of 16

ADA4862-3

V

www.BDTIC.com/ADI

APPLICATIONS

USING THE ADA4862-3 IN GAINS = +1, −1

The ADA4862-3 was designed to offer outstanding video
performance, simplify applications, and minimize board area.

The ADA4862-3 is a triple amplifier with on-chip feedback and
ga

in set resistors. The gain is fixed internally at G = +2. The
inclusion of the on-chip resistors not only simplifies the design
of the application but also eliminates six surface-mount
resistors, saving valuable board space and lowers assembly

+V

–V

+V

S

Figure 29.

S

10μF

0.01μF

0.01μF

10μF

S

10μF

0.01μF

0.01μF

V

OUT

05600-029

V

OUT

costs. A typical schematic is shown in

V

IN

R

T

GAIN OF +2

Figure 29. Noninverting Configuration (G = +2)

While the ADA4862-3 has a fixed gain of G = +2, it can be used
in other gain configurations, such as G = −1 and G = +1, which
are discussed next.

Unity-Gain Operation (Option 1)

There are two options for obtaining unity gain (G = +1). The
first is shown in Figure 30. In this configuration, the –IN input

in is left floating (feedback is provided via the internal 550 Ω),

p
and the input is applied to the noninverting input. The noise
gain for this configuration is 1. Frequency performance and
transient response are shown in Figure 31 through Figure 33.

IN

R

T

4

G = +1

= 150Ω

R

L

3

= 4pF

C

L

= 200mV p-p

V

OUT

2

1

0

–1

CLOSED-LOOP GAIN (dB)

–2

–3

–4

0.1 1000

1 10 100

FREQUENCY (MHz)

VS = +5V

VS = ±5V

Figure 31. Small Signal Unity Gain

3

G = +1

= 150Ω

R

2

L

= 4pF

C

L

= 2V p-p

V

OUT

1

0

–1

–2

–3

CLOSED-LOOP GAIN (dB)

–4

–5

–6

0.1 1000

1 10 100

FREQUENCY (MHz)

VS = +5V

VS = ±5V

Figure 32. Large Signal Gain +1

2.0

1.5

1.0

0.5

0

–0.5

OUTPUT VOLTAGE (V)

–1.0

–1.5

–2.0

CL= 9pF

CL= 6pF

CL= 4pF

G = +1

= 150Ω

R

L

V

= 2V p-p

OUT

= ±5V

V

S

TIME = 5ns/DIV

Figure 33. Large Signal Transient Response for Various Capacitor Loads

05600-053

05600-002

05600-020

10μF

–V

S

GAIN OF +1

05600-032

Figure 30. Unity Gain of Option 1

Rev. A | Page 11 of 16

ADA4862-3

www.BDTIC.com/ADI

Option 2

Another option exists for running the ADA4862-3 as a unity­gain amplifier. In this configuration, the noise gain is 2, see
Figure 34. The frequency response and transient response for

nfiguration closely match the gain of +2 plots because the

this co
noise gains are equal. This method does have twice the noise
gain of Option 1; however, in applications that do not require
low noise, Option 2 offers less peaking and ringing. By tying the
inputs together, the net gain of the amplifier becomes 1.
Equation 1 shows the transfer characteristic for the schematic
shown in
shown i

which simplifies to V

Figure 34. Frequency and transient response are

n Figure 35 and Figure 36.

⎛

−

R

⎜

=

VV

i

O

⎜

R

G

⎝

V

IN

1

0

G = +1

= 150Ω

R

–1

L

–2

–3

GAIN (dB)

–4

–5

–6

–7

0.1

Figure 35. Frequency Response of Option 2

⎛

⎞

F

⎜

⎟

+

V

i

⎜

⎟

⎝

⎠

= Vi.

O

R

T

+

RR

F

R

G

R

G

GAIN OF +1

⎞

G

⎟

(1)

⎟
⎠

+V

S

10μF

0.01μF

R

F

0.01μF

10μF

–V

S

Figure 34. Unity Gain of Option 2

1 10 100

FREQUENCY (MHz)

V

OUT

05600-030

05600-027

1000

200

G = +1
V

= ±5V

S

150

R

= 150Ω

L

TIME = 2ns/DIV

100

50

0

–50

OUTPUT VOLTAGE (mV)

–100

–150

–200

Figure 36. Small Signals Transient Response of Option 2

+V

S

10μF

0.01μF

V

IN

R

T

0.01μF

10μF

–V

S

GAIN OF –1

V

OUT

05600-031

Figure 37. Inverting Configuration (G = −1)

2.0

1.5

1.0

0.5

0

–0.5

OUTPUT VOLTAGE (V)

–1.0

–1.5

–2.0

CL= 9pF

CL= 6pF

CL= 4pF

G = –1

= 150Ω

R

L

= 2V p-p

V

OUT

= ±5V

V

S

TIME = 5ns/DIV

Figure 38. Large Signal Transient Response for Various Capacitor Loads

05600-039

05600-017

Rev. A | Page 12 of 16

ADA4862-3

V

V

V

www.BDTIC.com/ADI

VIDEO LINE DRIVER

The ADA4862-3 was designed to excel in video driver
applications. Figure 39 shows a typical schematic for a video

iver operating on a bipolar supplies.

dr

+V

S

10μF

0.1μF

–

ADA4862-3

+

75Ω

CABLE

IN

75Ω

0.1μF

10μF

–V

S

Figure 39. Video Driver Schematic

In applications that require two video loads be driven
simultaneously, the ADA4862-3 can deliver. Figure 40 shows

e ADA4862-3 configured with dual video loads. Figure 41

th

ws the dual video load performance.

sho

+V

S

10μF

0.1μF

7

–

2

8

6

+

0.1μF

10μF

–V

S

VS = +5V

75Ω

CABLE

IN

75Ω

Figure 40. Video Driver Schematic for Two Video Loads

8

G = +2
R

= 75Ω

L

7

C

= 4pF

L

V

OUT

6

5

4

3

CLOSED-LOOP GAIN (dB)

2

1

= 2V p-p

75Ω

75Ω

75Ω

75Ω

CABLE

75Ω

CABLE

75Ω

CABLE

VS = ±5V

75Ω

75Ω

75Ω

V

OUT

V

V

05600-033

OUT

OUT

1

2

05600-034

SINGLE-SUPPLY OPERATION

The ADA4862-3 can also operate in single-supply applications.
Figure 42 shows the schematic for a single 5 V supply video

iver. Resistors R2 and R4 establish the midsupply reference.

dr
Capacitor C2 is the bypass capacitor for the midsupply
reference. Capacitor C1 is the input coupling capacitor, and C6
is the output coupling capacitor. Capacitor C5 prevents constant
current from being drawn through the internal gain set resistor.
Resistor R3 sets the circuits ac input impedance.

For more information on single-supply operation of op amps,

www.analog.com/library/analogDialogue/a

see

rchives/35-

02/avoiding/.

C2

1μF

R4

R2

50kΩ

50kΩ

+5V

R3

1kΩ

IN

R1

50Ω

C1

22μF

22μF

C5

Figure 42. Single-Supply Vide

+5V

C3

2.2μF

C4

0.01μF

–V

S

o Driver Schematic

C6

220μF

R5

75Ω

ADA4862-3

R6
75Ω

V

OUT

05600-035

POWER DOWN

The ADA4862-3 is equipped with an independent Power Down
pin for each amplifier allowing the user to reduce the supply
current when an amplifier is inactive. The voltage applied to the

pin is the logic reference, making single-supply applications

−V

S

useful with conventional logic levels. In a typical 5 V single­supply application, the −V
The amplifiers are powered down when applied logic levels are
greater than −V

+ 1 V. The amplifiers are enabled whenever the

S

disable pins are left either floating (disconnected) or the
applied logic levels are lower than 1 V above −V

pin is connected to analog ground.

S

.

S

1

0

0.1

1 10 100

FREQUENCY (MHz)

Figure 41. Large Signal Frequency Response for Various Supplies, R

1000

= 75 Ω

L

05600-008

Rev. A | Page 13 of 16

ADA4862-3

www.BDTIC.com/ADI

LAYOUT CONSIDERATIONS

As is the case with all high speed applications, careful attention
to printed circuit board layout details prevents associated board
parasitics from becoming problematic. Proper RF design
technique is mandatory. The PCB should have a ground plane
covering all unused portions of the component side of the
board to provide a low impedance return path. Removing the
ground plane on all layers from the area near the input and
output pins reduces stray capacitance. Termination resistors and
loads should be located as close as possible to their respective
inputs and outputs. Input and output traces should be kept as
far apart as possible to minimize coupling (crosstalk) though
the board. Adherence to microstrip or stripline design
techniques for long signal traces (greater than about 1 inch) is
recommended.

POWER SUPPLY BYPASSING

Careful attention must be paid to bypassing the power supply
pins of the ADA4862-3. High quality capacitors with low
equivalent series resistance (ESR), such as multilayer ceramic
capacitors (MLCCs), should be used to minimize supply voltage
ripple and power dissipation. A large, usually tantalum, 10 μF to
47 μF capacitor located in proximity to the ADA4862-3 is
required to provide good decoupling for lower frequency
signals. In addition, 0.1 μF MLCC decoupling capacitors should
be located as close to each of the power supply pins as is
physically possible, no more than 1/8 inch away. The ground
returns should terminate immediately into the ground plane.
Locating the bypass capacitor return close to the load return
minimizes ground loops and improves performance.

Rev. A | Page 14 of 16

ADA4862-3

www.BDTIC.com/ADI

OUTLINE DIMENSIONS

8.75 (0.3445)

8.55 (0.3366)

4.00 (0.1575)

3.80 (0.1496)

0.25 (0.0098)

0.10 (0.0039)

COPLANARITY

0.10

CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS
(IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN

14

1

1.27 (0.0500)
BSC

0.51 (0.0201)

0.31 (0.0122)

COMPLIANT TO JEDEC STANDARDS MS-012-AB

Figure 43. 14-Lead Standard Small Outline Package [SOIC_N]

Dimensions shown in millimeters and (inches)

8

6.20 (0.2441)

7

5.80 (0.2283)

1.75 (0.0689)

1.35 (0.0531)

SEATING
PLANE

Nar

row Body

(R-14)

0.25 (0.0098)

0.17 (0.0067)

0.50 (0.0197)

0.25 (0.0098)

8°
0°

1.27 (0.0500)

0.40 (0.0157)

× 45°

ORDERING GUIDE

Model Temperature Range Package Description Ordering Quantity Package Option

ADA4862-3YRZ
ADA4862-3YRZ-RL
ADA4862-3YRZ-RL7

1

Z = Pb-free part.

1

1

1

–40°C to +105°C 14-Lead SOIC_N 1 R-14
–40°C to +105°C 14-Lead SOIC_N 2,500 R-14
–40°C to +105°C 14-Lead SOIC_N 1,000 R-14

Rev. A | Page 15 of 16

ADA4862-3

www.BDTIC.com/ADI

NOTES

© 2005 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D05600–0–8/05(A)

Rev. A | Page 16 of 16